# Light-by-Light Scattering Constraint on Born-Infeld Theory

## TL;DR

The paper uses ATLAS light-by-light scattering data to set new lower bounds on the mass scale of Born-Infeld extensions of QED and the Standard Model, significantly tightening previous constraints.

## Contribution

It provides the first direct experimental constraints on the Born-Infeld theory parameters using LHC data, improving previous bounds by a large margin.

## Key findings

- Mass scale of Born-Infeld QED > 100 GeV
- Mass scale of nonlinear U(1)_Y > 90 GeV
- Lower limit on magnetic monopole mass > 11 TeV

## Abstract

The recent measurement by ATLAS of light-by-light scattering in LHC Pb-Pb collisions is the first direct evidence for this basic process. We find that it requires the mass scale of a nonlinear Born-Infeld extension of QED to be $\gtrsim 100$~GeV, a much stronger constraint than those derived previously. In the case of a Born-Infeld extension of the Standard Model in which the U(1)$_{\rm Y}$ hypercharge gauge symmetry is realized nonlinearly, the limit on the corresponding mass scale is $\gtrsim 90$~GeV, which in turn imposes a lower limit of $\gtrsim 11$~TeV on the magnetic monopole mass in such a U(1)$_{\rm Y}$ Born-Infeld theory.